Numerical optimisation of loss system with retrial phenomenon in cellular networks

: In this study, we extend upon the model by Haring et al. (2001) by introducing retrial phenomenon in multi-server queueing system. When the most g number of guard channels are available, it allows new calls to join the retrial group. This retrial group is called orbit and can hold a maximum of m retrial calls. The impact of retrial over certain performance measures is numerically investigated. The focus of this work is to construct optimisation problems to determine the optimal number of channels, the optimal number of guard channels and the optimal orbit size. Further, it has been emphasised that the proposed model with retrial phenomenon reduces the blocking probability of new calls in the system.